Decoding Tetra

[N.Watts]

Hi is there any way to decode Tetra communications on my Uniden UBC3300xlt
scanner please.
Cheers
Nigel

[David Norris]

Post by N.Watts
Hi is there any way to decode Tetra communications on my Uniden UBC3300xlt
scanner please.
Cheers
Nigel

No way I'm afraid. Even a Tetra set canot do so without knowing the
encryption key.

[Mungo]

Post by David Norris
No way I'm afraid. Even a Tetra set canot do so without knowing the
encryption key.

Oh come on, lets be realistic about this - of course there is a way to crack
Tetra. Just as there is a way to crack any encryption given enough time
and/or processing power. It currently takes about 15 minutes to crack 128
bit encryption, and as most Police Tetra systems run at a mere 40 bit,
well - you decided.

The key (ahem, no pun intended) is to wait for an glitch on the process that
will help crack the whole key.

An interesting read on the subject is "Body of Secrets" by James Bamford, it
covers this very topic and how organisations like the NSA in the States has
been doing this for a long long time.

/mung.

[Pete]

Oh don't start , please :-)), you will only have that know-all Mike GW8IJT
spouting his usual crap again.

Post by Mungo

Post by David Norris
No way I'm afraid. Even a Tetra set canot do so without knowing the
encryption key.

Oh come on, lets be realistic about this - of course there is a way to
crack Tetra. Just as there is a way to crack any encryption given enough
time and/or processing power. It currently takes about 15 minutes to crack
128 bit encryption, and as most Police Tetra systems run at a mere 40 bit,
well - you decided.
The key (ahem, no pun intended) is to wait for an glitch on the process
that will help crack the whole key.
An interesting read on the subject is "Body of Secrets" by James Bamford,
it covers this very topic and how organisations like the NSA in the States
has been doing this for a long long time.
/mung.

[Chris Eilbeck]

Post by Mungo

Post by David Norris
No way I'm afraid. Even a Tetra set canot do so without knowing the
encryption key.

Oh come on, lets be realistic about this - of course there is a way
to crack Tetra. Just as there is a way to crack any encryption given
enough time and/or processing power. It currently takes about 15
minutes to crack 128 bit encryption, and as most Police Tetra
systems run at a mere 40 bit, well - you decided.

Cites?

Chris

[David Norris]

Post by Mungo

Post by David Norris
No way I'm afraid. Even a Tetra set canot do so without knowing the
encryption key.

Oh come on, lets be realistic about this - of course there is a way to
crack Tetra. Just as there is a way to crack any encryption given enough
time and/or processing power. It currently takes about 15 minutes to crack
128 bit encryption, and as most Police Tetra systems run at a mere 40 bit,
well - you decided.
The key (ahem, no pun intended) is to wait for an glitch on the process
that will help crack the whole key.
An interesting read on the subject is "Body of Secrets" by James Bamford,
it covers this very topic and how organisations like the NSA in the States
has been doing this for a long long time.
/mung.

Any idea of the size of 2^128?

[String]

Post by Mungo
Oh come on, lets be realistic about this - of course there is a way to crack
Tetra. Just as there is a way to crack any encryption given enough time
and/or processing power. It currently takes about 15 minutes to crack 128
bit encryption, and as most Police Tetra systems run at a mere 40 bit,
well - you decided.

Err there are LOTS of different algorithms that take massively varying
amount of time to crack. 15 mins for a 128bit brute force is not possible
on a home computer no matter what the algorithm is.

Post by Mungo
The key (ahem, no pun intended) is to wait for an glitch on the process
that will help crack the whole key.

In the same way GSM is flawed.... And you still cant get home/public use
decoders.

[Peter Hunt]

Post by Mungo
Oh come on, lets be realistic about this - of course there is a way to crack
Tetra. Just as there is a way to crack any encryption given enough time
and/or processing power. It currently takes about 15 minutes to crack 128
bit encryption, and as most Police Tetra systems run at a mere 40 bit,
well - you decided.

15 minutes? Make that 15 years ;-)))))

Peter.

[Prometheus]

Post by Mungo

Post by David Norris
No way I'm afraid. Even a Tetra set canot do so without knowing the
encryption key.

Oh come on, lets be realistic about this - of course there is a way to crack
Tetra. Just as there is a way to crack any encryption given enough time
and/or processing power. It currently takes about 15 minutes to crack 128
bit encryption,

Just what computer do you think can try
340,282,366,920,938,463,463,374,607,431,770,000,000 codes in fifteen
minutes? AND remember it is not enough to try each code on one received
binary word only, since every potential key will produce an output you
have to try each key on a block and determine if the output is clear
language or not.

[harrogate2]

Post by Prometheus

Post by Mungo

Post by David Norris
No way I'm afraid. Even a Tetra set canot do so without knowing the
encryption key.

Oh come on, lets be realistic about this - of course there is a way to crack
Tetra. Just as there is a way to crack any encryption given enough time
and/or processing power. It currently takes about 15 minutes to crack 128
bit encryption,

Just what computer do you think can try
340,282,366,920,938,463,463,374,607,431,770,000,000 codes in fifteen
minutes? AND remember it is not enough to try each code on one

received

Post by Prometheus
binary word only, since every potential key will produce an output you
have to try each key on a block and determine if the output is clear
language or not.
--
Ian G8ILZ

Add to that that it is probably a rolling code as well.......

As was said at the start, essentially impossible. Why do you think the
keys are issued by GCHQ...........?


--
Woody

harrogate2 at ntlworld dot com

[Chris Eilbeck]

Post by harrogate2
As was said at the start, essentially impossible. Why do you think
the keys are issued by GCHQ...........?

Are they? Who told you that?

Chris

[harrogate2]

Post by Chris Eilbeck

Post by harrogate2
As was said at the start, essentially impossible. Why do you think
the keys are issued by GCHQ...........?

Are they? Who told you that?
Chris
--
Chris Eilbeck
MARS Flight Crew

http://www.mars.org.uk/

Post by Chris Eilbeck
UKRA #1108 Level 2

UYB

Post by Chris Eilbeck
Tripoli UK Member #9527

LSMR

(a) They were for MASC

(b) Since it is so difficult to crack Tetra encryption, if you want to
listen in (as they do) the best way is to know the key in advance -
and the best way to know it is to issue it. QED


--
Woody

harrogate2 at ntlworld dot com

[Chris Eilbeck]

Post by harrogate2

Post by Chris Eilbeck

Post by harrogate2
As was said at the start, essentially impossible. Why do you think
the keys are issued by GCHQ...........?

Are they? Who told you that?

(a) They were for MASC

I was under the impression MASC was unkeyed.

Post by harrogate2
(b) Since it is so difficult to crack Tetra encryption, if you want
to listen in (as they do) the best way is to know the key in advance
- and the best way to know it is to issue it. QED

GCHQ don't trust our law enforcement authorities? And they call me a
cynic ;)

Chris

[String]

Post by Chris Eilbeck
I was under the impression MASC was unkeyed.

Most MASC sets issued were used for their entire life on the factory default
keys.

Post by Chris Eilbeck

Post by harrogate2
(b) Since it is so difficult to crack Tetra encryption, if you want
to listen in (as they do) the best way is to know the key in advance
- and the best way to know it is to issue it. QED

You dont need to brute/crack the encryption to listen in on tetra, simply
get access for the talkgroup and get a proper connection.

[harrogate2]

Post by String

Post by Chris Eilbeck
I was under the impression MASC was unkeyed.

Most MASC sets issued were used for their entire life on the factory default
keys.

MASC was very much keyed and the factory default was ALWAYS changed so
that (a) anyone with factory default keys could not listen in and (b)
beacuse GCHQ actually monititored key usage and cautioned the users if
they were not up to date.

The fact that many forces only used MASC in chase or similar
situations (the converse of best use for MASC) may have something to
do with it.


--
Woody

harrogate2 at ntlworld dot com

[String]

Post by harrogate2
The fact that many forces only used MASC in chase or similar
situations (the converse of best use for MASC) may have something to
do with it.

I can definately think of 2 forces that used standard factory keyed MASC
sets on surveillance.

[String]

AND remember it is not enough to try each code on one received

Post by Prometheus
binary word only, since every potential key will produce an output you
have to try each key on a block and determine if the output is clear
language or not.

Not quite. TETRA implementation performed here is the air interface is (or
CAN be) encrypted but the voice isnt. Thats why customs and PNSI amongst
others have reservations about it. Some systems are using 128bit IDEA on
the voice but not in Airwave.

[Chris Eilbeck]

Post by String
Not quite. TETRA implementation performed here is the air interface
is (or CAN be) encrypted but the voice isnt. Thats why customs and
PNSI amongst others have reservations about it. Some systems are
using 128bit IDEA on the voice but not in Airwave.

The air interface is encrypted (for voice, data and signalling) but
the links in the network aren't, much like GSM.

Chris

[Prometheus]

Post by Chris Eilbeck

Post by String
Not quite. TETRA implementation performed here is the air interface
is (or CAN be) encrypted but the voice isnt. Thats why customs and
PNSI amongst others have reservations about it. Some systems are
using 128bit IDEA on the voice but not in Airwave.

The air interface is encrypted (for voice, data and signalling) but
the links in the network aren't, much like GSM.

You could try one of these:

http://www.cesg.gov.uk/site/crypto/media/Sectera.pdf

[Chris Eilbeck]

Post by Prometheus

Post by Chris Eilbeck

Post by String
Not quite. TETRA implementation performed here is the air interface
is (or CAN be) encrypted but the voice isnt. Thats why customs and
PNSI amongst others have reservations about it. Some systems are
using 128bit IDEA on the voice but not in Airwave.

The air interface is encrypted (for voice, data and signalling) but
the links in the network aren't, much like GSM.

http://www.cesg.gov.uk/site/crypto/media/Sectera.pdf

Looks like a nice device.

Chris

[String]

Post by Chris Eilbeck

Post by Prometheus
http://www.cesg.gov.uk/site/crypto/media/Sectera.pdf

Looks like a nice device.

Mobile phone with encryption module by the looks of it.
As in another layer on top of GSM.

[Mike GW8IJT]

Post by N.Watts
Hi is there any way to decode Tetra communications on my Uniden UBC3300xlt
scanner please.
Cheers
Nigel

No.
Next question, please.
Regards Mike.

[shortwave]

Post by N.Watts

Post by N.Watts
Hi is there any way to decode Tetra communications on my Uniden

UBC3300xlt

Post by N.Watts
scanner please.
Cheers
Nigel

No.
Next question, please.
Regards Mike.
--
North Wales should be independent from South Wales.

You sound a right asshole!
I agree with you on one point though, S-Wales should be independant from
N-Wales, N-Wales is full of pig ignorant, bad mannered, unfriendly back
stabbers, I've yet to meet a decent one yet
SW

[Mike GW8IJT]

Post by shortwave

Post by N.Watts

Post by N.Watts
Hi is there any way to decode Tetra communications on my Uniden

UBC3300xlt

Post by N.Watts
scanner please.
Cheers
Nigel

No.
Next question, please.
Regards Mike.
--
North Wales should be independent from South Wales.

You sound a right asshole!
I agree with you on one point though, S-Wales should be independant from
N-Wales, N-Wales is full of pig ignorant, bad mannered, unfriendly back
stabbers, I've yet to meet a decent one yet
SW

Nice to talk to you as well.
Regards Mike.

[String]

Post by Mike GW8IJT

Post by shortwave
You sound a right asshole!
I agree with you on one point though, S-Wales should be independant

from

Post by shortwave
N-Wales, N-Wales is full of pig ignorant, bad mannered, unfriendly

back

Post by shortwave
stabbers, I've yet to meet a decent one yet
SW

Nice to talk to you as well.
Regards Mike.

Can we give the slum town of newport to England while we're at it?

[Pete]

Post by String

Post by Mike GW8IJT

Post by shortwave
You sound a right asshole!
I agree with you on one point though, S-Wales should be independant

from

Post by shortwave
N-Wales, N-Wales is full of pig ignorant, bad mannered, unfriendly

back

Post by shortwave
stabbers, I've yet to meet a decent one yet
SW

Nice to talk to you as well.
Regards Mike.

Can we give the slum town of newport to England while we're at it?

Newport WAS English, that is before the boundries were changed. It then
became Newport Gwent. Before it was Newport Monmouthshire. You pathetic
Welsh Hill-Billy ass-holes decided YOU wanted Newport as part of Wales. I
doubt for one moment that the residents of Newport are very pleased to be
part of the pathetic Welsh Nation. Personally, I cannot abide Wales, it is a
right shit-hole, especially the valleys, Christ! What a dump. And the less
said about North Wales the better.
Pete